/*
 * Copyright 2010-2011, David George, Licensed under the Apache License,
 * Version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package org.magneato.utils;

import java.io.File;
import java.io.FileFilter;

/**
 * Helper class to filter template files from directory listing
 * 
 * @author David B George
 */
public class TemplateFilter implements FileFilter {
	public final static String PREQUEL = "x.";
	
	public boolean accept(File file) {
		if (file != null && file.isFile()) {
			String fileName = file.getName();
			return (fileName.startsWith(PREQUEL) && fileName
					.length() > 4) ? true : false;
		}

		return false;
	}

	/**
	 * Helper class, returns the extension portion of the file's name .
	 * 
	 * @see #getExtension
	 * @see FileFilter#accept
	 */
	static public String getExtension(File f) {
		if (f != null) {
			String filename = f.getName();
			int i = filename.lastIndexOf('.');
			if (i > 0 && i < filename.length() - 1) {
				return filename.substring(i + 1).toLowerCase();
			}
		}
		return null;
	}
}